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Types of excreta disposal system
Published in Sandy Cairncross, Richard Feachem, Environmental Health Engineering in the Tropics, 2018
Sandy Cairncross, Richard Feachem
A septic tank is a watertight settling tank to which wastes are carried by water flushing down a short sewer. A septic tank does not dispose of wastes; it only helps to separate and digest the solid matter. The liquid effluent flowing out of the tank remains to be disposed of, normally by a soakage pit or drainfield, and the sludge accumulating in the tank must be periodically removed.
Handling, Safety, and Environmental Aspects
Published in Eric Jungermann, Norman O.V. Sonntag, Glycerine, 2018
G. N. McDermott (Procter & Gamble Co.), in Bailey’s Industrial Oil and Fat Products [18] gives the BOD of lost glycerol from wastewaters in soap-making during the two operations of glycerol concentration and glycerol distillation as 15 and 5 mass BOD units, respectively, per 1000 units of glycerol. This data was obtained from mass quantities of pollutant in wastewaters following removal of floatable oil by passing through gravity settling tanks. Further, the suspended solids in these wastewaters from these materials were 2 and 2 units, respectively, per 1000 units of glycerol. Based upon average costs (1982) of 8¢/lb for the removal of one pound of BOD and of 6¢/lb for the removal of one pound of suspended solids, the processing costs alone could be approximated as $0.00135/lb glycerol produced. An additional cost of about 15¢/lb per 1000 gallons of wastewater processed must be imposed upon this cost plus the cost of the water itself. The total cost for the loss of one pound of glycerol through wastewater can be approximated as 50.2¢/lb, assuming that glycerol is valued at 50¢/lb.
What is iodine?
Published in Tatsuo Kaiho, Iodine Made Simple, 2017
Brine is drawn up from 500 to 2,000 m underground along with natural gas, and isolated from the natural gas using a separator. Next, sand and other impurities are removed from the brine in a settling tank, and then the brine is sent to the iodine production process.
CUSUM chart method for continuous monitoring of antifouling treatment of tubular heat exchangers in open-loop cooling seawater systems
Published in Biofouling, 2020
David Boullosa-Falces, Sergio García, David Sanz, Alfredo Trueba, Miguel Angel Gomez-Solaetxe
The cooling pump extracted seawater from the Santander Bay (43°28’N, 3°48’W) at a depth of 3 m by two centrifugal pumps connected in series (ITUR AU-MI 1.5/10, Zarautz, Spain). In order to separate the water from organic substances such as algae or fine particles, the seawater was subjected to macro-filtration and decanting processes. For this purpose, a strainer filter suction (strainer element with 5.0 mm hole size) was installed in the seawater pump. After this, the seawater was pumped to settling tank (1 m3) where the sand and other heavier particles settled at the bottom and floating particles were drained from the surface. Then, the seawater was transported to a second tank (1 m3) which included a turbulence chamber, from where the water passed through filters that kept the macroparticles in a desilting chamber, and then the filtered seawater was pumped at 1.9 bar through the circulation pump (Grundfos CHI 4-50 A WG, Algete, Spain) towards the heat exchanger tubes.
Frictional drag measurements of large-scale plates in an enhanced plane channel flowcell
Published in Biofouling, 2020
Serkan Turkmen, Mehmet Atlar, Irma Yeginbayeva, Simon Benson, John A Finlay, Anthony S. Clare
A 2,700 mm long (L) and 180 mm wide (W) stainless steel measurement section runs between the contraction section (contraction ratio = 34.7:1) and the settling tank. Two identical UNEW standard test panels (L = 0.6 m and W = 0.22 m) can be placed at the top and bottom of the pressure drop section. This is important because the flow developed between two flat panels will be symmetrical with respect to the centreline of the channel under a constant pressure gradient (dp/dx) and zero gravity.
Dietary inclusion of royal jelly modulates gene expression and activity of oxidative stress enzymes in zebrafish
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2021
Ercüment Aksakal, Deniz Ekinci, Claudiu T. Supuran
Mains water in the model organism unit was used as the water material in the study. Before the water was supplied to the system, it was passed through eight different filters and aerated for 2 days in the settling tanks. The water parameters are given in Table 1.